Apparatus for drawing vitreous tubes and rods



July 29, 1952 2,604,733

A. F. CASLER APPARATUS FOR DRAWING VITREOUS TUBES AND RODS Filed July 17, 1950 2 SHEETSSHEET l Inven bov: Adrien E Caster", Jog Un rr. A"

y 29, 1952 A. F. CASLER ,60 ,7

' APPARATUS FOR DRAWING VITREOUS TUBES AND RODS I Filed July 17, 1950 2 SHEETS-SHEET 2 mmuuu swc k.

His A=t=towweg Adrien F. Casber,

Patented July 29, 1952 UNITED STATES PATENT ornce APPARATUS'FOR DRAWING VITREOUS TUBES AND RODS Adrien F. (Easier, East Cleveland, Ohio, as'signor to General Electric Company, a. corporation-of New York Application July 17, 1950, Serial-No. 174,309

"Claims. 1

My invention relates to apparatus for drawing vitreous tubing or rod and more particularly to tractor apparatus for withdrawing vitreous tube or red from the end of a blow pipe or'mandrel.

In the manufacture of vitreous tube and rod in accordance with the method disclosed by Banner in United States Patent 1,219,709, means are provided for pulling tube orrod off the lower end of an inclined mandrel located directly below the outlet of a melting furnace. The rate at which the vitreous tube or rod is withdrawn is to a certain extent controlling as to size and condition of said tube or rod produced inasmuch as said tube or rod is usually materially changed in shape in the course of its passage from the end of the mandrel to its final form in the general vicinity of the drawing means some distance away.

One object of my invention is to provide apparatus for drawing tube and rod in a satisfactory manner at extremely high rates of speed.

Another object of my invention is to provide apparatus best adapted to draw uniformly shaped and straight tube and rod at very high rates of speed. v

Still another object of my invention is to provide apparatus for satisfactorily drawing vitreous' tube or rod at high rates of speed which apparatus is particularly wear free and adapted to rema n in adjustment for relatively long periods of operation.

The preferred form of my apparatus effects the advance or drawing of the vitreous tube or rod by means of the rotation of successive pairs of wheels engaging opposite sides thereof. The wheels are each rotated about their axes to effect the drawing motion in the vitreous tube or rod and also have lateral movements which oscillate them across the path of movement of the tube or rod so that different portions of the may be covered with aresilient heat resistant material.

It is also preferred that each driving Wheel-in a pair be oppositely skewed to the direction-ofmovementof the tube or rod so that said tube or rod is simultaneously twisted about its longitudinal axis atthe same time as it is moved longitudinally and, accordingly, is straightened.

Still other-objects-and advantages of my invention will appear from the following description of the species thereof shown in the drawing.

In the drawing, Figs. 1 and 2 are plan and side elevations, respectively, of one example of the vitreous tube and rod drawing apparatus of the invention; Fig. 3 is an end elevation of said apparatus after the removal of one of the guiding means; Fig. 4' is a vertical section on a larger scale through one of the guiding'means; and Fig. 5 is a partiallyexploded perspective view of the meansfor oscillating the drive wheels'axially.

The apparatus disclosed in the drawing is located some distance from the vitreous'tube-fc'rming mandrel (not shown) in the drawing alley and is positioned sufficiently far from the mandrel that it engages a cooled and therefore almost completely congealed portion of the vitreous tube I. The apparatus performs the function of withdrawing the vitreous tube 1- from the mandrel by means comprised of the three driven pairs of wheels 2, 3; 4-, 5 and 6, I which are arranged along successive lower and upper portions of the tube 1 and which are capable of rotating at a speed to advance said tube I longitudinally through the drawing alleyat the exceedingly fast rate of more than 2,000 feet per minute. The arrangementand speed of operation of the drawing apparatus are so established that the tube I takes its final set at the time it passes from engagement therewithand, accordingly, is still susceptible of minor changes in shape at the time it passes into engagement therewith. This latter condition in the tube l permits a straightening function to be performed by the drawing apparatus, an operation which is performed by having the lower wheels 2, 4', and 6 skewed in one direction with respect to the direction of travel of' the tube l and the upper wheels 3, 5, and I correspondingly skewed in the opposite directionso that the tube l is twisted around its longitudinal axis. All driving Wheels 2, 3, 4, 5, '6, and I have flat outer faces and are preferably covered with outer bands 8 of resilient heat-resisting material, suchas a silicone rubber, which'increases the friction between said wheels 2-'-|, inclusive, and the tube and which enables said wheels 2-1, inelusive, to grip said tube more securely without injury thereto. v V

The lower 'driving'fwheels 2', 4, and B are mount- "ed'upori corresponding shafts 9 held by respective journals in the carriage I0 and form a bed of fixed he'ig'htfor supporting the tube l, whereas, the upper driving wheels 3, 5, and 'I' are mounted upon corresponding shafts ll located within journals of corresponding arm's l2 pivoted on shafts Irena l4 held by said carriage land are capable of verucar movement to' produce the gripping force between lower and upper wheels 2, 4, 6 and 3, 5, I, respectively. Under the operating conditions illustrated in the drawing, wherein a small size tube I is being drawn, relatively little pressure is required between the lower and upper wheels 2, 4, 6 and 3, 5, I, respectively, to produce the required friction to advance the tube I and the full weight of the assemblies comprising the upper wheels 3, 5, and I, shafts II and the arms I2 is partially carried by studs I5 attached to the journal for shafts II. The studs I5 extend up through a fixed bar I6 attached by the bracket IT to the journals n the carriage Ill supporting the shafts I3 and I4 and are pulled upward by the expansion force of helical springs I8 located between said fixed bar I6 and the nuts I9 on the upper end of studs I5. Separate adjustable means are thereby provided for controlling the downward pressure of each of the upper driving wheels 3, 5, and I and,

accordingly, compensation can be made in said means for the additional downward or upward pull exerted in particular wheels 3, 5, and I by the driving means therefor. When more friction is required between the wheels '2-I, inclusive, 9

than can be provided by the weight of the upper wheels 3, 5, I and the associated assemblies comprised of the arms I2, as when considerably larger tube or rod is being drawn, downward pressure is applied against said assemblies by placing the spring I8 or a corresponding spring of different compression strength around that portion of the studs I between the fixed bar I6 and the arms I2. In this latter position, the spring I8, or its alternate, butts against the lower surface of the fixed bar I6 and bears directly against the arm I2 with its expansion force.

The driving force introduced in the wheels 2, 3, 4, 5, I5, and 1 is separately supplied thereto although it is introduced in the apparatus through the single drive shaft on the speed reducer 2| at the back of the solid support bed 22 of the apparatus and although it is carried through duplicate lower and upper driving means 23 and 23' extending from the speed reducer 2I to intermediate driving shafts 24 and I4, respectively, on the carriage I9 and associated with the lower and upper wheels 2, 4, 6 and 3, 5, I, respectively. The driving force for the upper .wheels 3, 5, and I, as is present in intermediate drive shaft I4 which also functions as the pivot for the arms I2, I2 holding the wheels 5 and I, is transferred through separate sprockets on the hub 25 and the chains 23, 21 and sprockets 28, '29

to the respective support shafts II, II for the wheels 5 and I and is'transferred through another sprocket on hub 25, chain 39, integral sprockets on a hub 3| on the pivot shaft I3, chain 32 and sprocket 33 on the support shaft I I to the wheel 3. The driving force for the lower wheels 2, 4, and 6, which force appears in the intermediate shaft 24, is transferred to the respective wheels 2, 4, and 6 through'a corresponding group of sprockets on the hub 34 and, although not completely shown, through other means including a shaft 35 corresponding to the shaft I3 shown in combination with the upper wheels 3, 5, and I. The angular relation ,of the intermediate drive shafts 24 and I4 associated withlthe lower and upper wheels 2, 4, 6 and 3, 5, I, respectively, and the driving shafts 35 and 31 of the speed reducer 2I is compensated for inthe lower and upper driving means 23 and 23' by universal couplings 38, 39 and 38', 39, whereassplined shafts 40 and 40? which are slidable longitudinally in corre spondingly grooved sleeves M and 4| allow changes in the relative position of the speed reducer '2I and the tube drawing wheel assembly held by the carriage Ill. The universal couplings 38 and 38 of the driving means 23 and 23' are, in turn, driven by the speed reducer 2I from duplicate worm gear wheels 42 and 42 meshing with the worm gear 43 on the main drive shaft 20 as indicated in the dot-dot lines in Fig. 3.

Wear and grooving of the outer periphery or face of the tube drawing wheels 2-I is retarded by a continuous lateral oscillation of the entire drawing wheel assembly supported by the carriage I0 which motion causes different laterally disposed peripheral portions of said wheels 2-I to contact the tube I in turn and which thereby spreads the contact area of the wheels 2-I to substantially the full width of the face thereof. The tube I is not pulled from its straight path through the apparatus by the lateral motion of the wheels 2-I in that said motion is relatively slow in comparison to the very rapid longitudinal motion of said tube I and since the tube I is held in place by guiding means comprised of the pairs of guide rolls 44 and 45 at the input and output ends of the apparatus.

The guide rolls 44 and 45, as shown in greater detail in Fig. 4, are correspondingly mounted upon ball bearings 46 carried by the pivot blocks 41 on the top end of the upstanding rods 48 on the slides 49 and normally remain at fixed positions on either side of the path of travel of the vitreous tube I. Each guide roll 44 or 45 is free to swing back out of the way should an enlargement, as for instance a stone, be embodied within an imperfect portion of said tube I, in that the rod 48 is pivoted upon a pin 50 held by the slide 49 which is slotted at 5| and 52 to allow said rod 48 to swing laterally with respect to said tube I. The expansion force of a spring 53 located between a washer 54 and the nuts 55 on the stud 55 normally keeps the roll 44 or 45 at a position determined by the engagement of an ear 51 on the pivot blocks 41 with the nut 58 on the stud 53 which is permanently attached to slide 49. Provision is made in the knob 59 and the screw 60 for spacing the guide rolls 44 and 45 according to the size of tube I being drawn. The operation of respacing said rolls 44 and 45 consists only in turning the knob 59 manually so that the opposite pitch of the threads on the screw 60 move the slides 49 apart or closer together on the support bracket 6| which is fastened to the edge of the bed 22 of the apparatus.

The lateral motion of the tube drawing wheels 2-I is the separate function of the electric motor '62 and associated means located over the center portion of the bed plate 22 and effect the oscillation of the slide '63, the support for the carriage III, in the ways provided on the bed plate 22 by the gibs 64 and 65. The forward end of the slide 63 overhangs the edge of the bed plate 22 adjacent the drawing wheels 2-I where additional support is provided by the angle iron 66';

whereas, the opposite end of said slide 63 is connected by means of the bracket 61 and bolt 58 to the bell crank 69 which is, in turn, attached by bolt Ill to a slide II in the assembly including the electric motor 62. Other portions of the operating means for the slide 63 as shown in Fig. 5 consist of the commercial speed reducer I2 (not shown in detail) which is attached to the lower end of the electric motor 62 and the edge cam I3 on the lower end of the driven shaft I4 of the speed reducer I2 which cam I3 causes the rollers l5 and 76 and, accordingly, the slide H, the support therefor, to be moved back and forth in proportion to the difference in the form thereof. The slide 'H is confined in ways within the block Ti by the spacer plate 18 which has a pocket 19 in the center accommodating the cam 13 and the rollers 15 and 16 and turns the bell crank 69 about a pivot bolt 80 extending upward from a flange 8! attached to the bed plate 22. The electric motor 62 and speed reducer 12 are mounted one above the other on the housing 82 which is bolted to the spacer plate 18 and the block ll.

Although a preferred embodiment of the invention has been disclosed, it will be understood that the invention is not to be limited to the specific construction and arrangement of parts shown, but that they may be widely modified within the spirit and scope of said invention as defined by the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for drawing vitreous tube or rod comprising pairs of cooperating driven wheels with peripheral faces against opposite sides of a vitreous tube or rod for eifecting the longitudinal advance thereof, a carriage for supporting one wheel of each pair, means pivoted upon said carriage for holding each of the cooperating wheels, the wheels being skewed with respect to the path of travel of the rod or tube, the wheels of each pair being oppositely skewed, means for rotating the wheels, and means for oscillating the carriage transversely to the path of travel of the tube or rod to cause different portions of their faces to engage said tube or rod in turn.

2. Apparatus for drawing vitreous tube or red comprising pairs of cooperating driven wheels with peripheral faces against opposite sides of a vitreous tube or rod for effecting the longitudinal advance thereof, a carriage for supporting one wheel of each pair, means pivoted upon said carriage for holding each of the cooperating wheels, the wheels being skewed with respect to the path of travel of the rod or tube, the wheels of each pair being oppositely skewed, means for rotating the wheels, slide ways located to the side of the path of travel of the tube or rod and extending transversely thereto, a slide located in the ways for supporting the carriage, and means for oscillating the slide to cause different portions of the faces of said wheels to engage said tube or rod in turn.

3. Apparatus for drawing vitreous tube or rod comprising pairs of cooperating driven wheels with peripheral faces against opposite sides of a tube or rod, a carriage for supporting one wheel of each pair in planes or rotation skewed to the longitudinal extent of the tube or rod, means pivoted on the carriage for holding each of the cooperating wheels in planes of rotation skewed oppositely to the first-mentioned wheels, means for rotating the wheels to effect both the longitudinal advance and the rotation of the tube or rod, guide means located along the path of travel of the tube or rod at positions on opposite sides of the wheels for preventing said tube or rod from moving laterally, and means for oscillating the carriage transversely to the path of travel of the tube or rod to cause different portions of the faces of said wheels to engage said tube or rod in turn.

4. Apparatus for drawing vitreous tube or rod comprising pairs of cooperating wheels with peripheral faces against opposite sides of a vitreous tube or rod, a carriage for supporting one wheel of each pair in planes of rotation skewed to the longitudinal extent of the tube or rod, means pivoted on the carriage for holding each of the cooperating wheels in planes of rotation skewed oppositely to the first-mentioned wheels, means mounted on said carriage for rotating the wheels to effect both the longitudinal advance and the rotation of the tube or rod, operating means located at a fixed position adjacent the carriage and having extensible coupling attached to said last-mentioned means, and means for oscillating the carriage transversely to the path of travel of the tube or rod to cause different portions of the faces of said wheels to engage said tube or rod in turn.

5. Apparatus for drawing vitreous tube or rod comprising pairs of cooperating wheels with peripheral faces against opposite sides of a vitreous tube or rod, a carriage for supporting one wheel of each pair in planes of rotation skewed to the longitudinal extent of the tube or rod, means pivoted on the carriage for holding each of the cooperating wheels in planes of rotation skewed oppositely to the first-mentioned wheels, separate means on said carriage for rotating the wheels on corresponding sides of the tube or rod to effect both the longitudinal advance and the rotation of the tube or rod, operating means located at a fixed position adjacent the carriage and having extensible couplings attached to each of said last-mentioned means, and means for oscillating the carriage transversely to the path of travel of the tube or rod to cause different portions of the faces of said wheels to engage said tube or rod in turn.

ADRIEN F. CASLE-R.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,220,201 Danner Mar. 27, 1917 1,702,969 Helland Feb. 19, 1929 2,009,326 Sanchez-Vello July 23, 1935 2,024,447 Hendrickson Dec. 17, 1935 2,438,448 Morton et a1. Mar. 23, 1948 2,525,590 Collins Oct. 10, 1950 OTHER REFERENCES 1949 Modern Plastics Encyclopedia and Engineers Handbook, pages 252 and 253, published by Plastics Catal. Corp., New York. 

